Can I manually edit the points along a path or curve in the blender UI?
In Edit mode, press N or click View -> Properties to open the properties panel. Then, under Transform you will have Control Point. This is the coordinates of the currently selected point. If you have several points selected, it will change to Median and editing the values, will move all selected points so that their median is located at the specified coordinates.

  

By Properties panel, I'm refering to the area that I marked with red edges in the image below. If it's not visible, you need to open it, either by pressing N or by clicking View -> Properties